Vehicle mounted cameras and other optical assemblies have typically been employed in specialty applications such as law enforcement, surveillance, television or film applications, etc. In such applications, there is little concern with suitability of the optical assembly and related vehicle mounting system for volume manufacturing. Also, there is relatively little concern for aesthetics or creation of a functional yet unobtrusive design. Rather, the desire is usually to allow a user in the vehicle to have ready access to, and control of, the camera or other device, and an obtrusive design is tolerated if not desired.
Relatively recently, however, systems have been proposed which could be incorporated in virtually all vehicles for safety or driver convenience and which require a camera or other optical assembly to be mounted in the vehicle. For such applications, the optical assembly must be unobtrusive as well as functional. Also, the assembly must be adapted for ease of service or replacement. Once example of such a safety application which is very important is a lane departure warning system.
When driving on a roadway, one of the primary requirements for safe transportation is the ability to keep the vehicle in the lane of travel. Of course, in most situations a driver can safely accomplish this task by paying attention to the road. Sometimes, however, a driver fails to keep the vehicle in the desired lane (e.g., the driver falls asleep, the driver is distracted with the radio or other vehicle system, the driver is diverted by other vehicles or roadside conditions, etc.). Therefore, systems have been proposed which can issue a warning to the driver if the vehicle is proceeding outside of the designated lane.
This type of warning system requires an optical assembly which can be mounted on the vehicle. Other driver assist or safety systems have also been proposed which require a vehicle mounted optical assembly such as a camera. However, implementation of such a vehicle mounted optical assembly presents several problems. First, for safety reasons, the assembly must be mounted in such a way so as not to impede the view of the road to the driver. Further, the device may have to be able to meet vehicle laws regulating obstruction to viewing which are found in various jurisdictions. Second, the housing for the electronics and optical equipment should be easily removable for repair, reprogramming, testing, etc. Third, the optics in the electronics/camera enclosure is negatively affected by any vision obstruction including fogging of the windshield or the lens element of the device.
Therefore, a need presently exists for an optical assembly which may be employed in vehicles and which overcomes the above-noted problems.